1. Field of the Invention
The present invention relates to an attachment structure for a joint boot to be attached to a constant velocity universal joint for transmitting rotary driving force.
2. Description of the Related Art
A constant velocity universal joint is generally used in order to transmit the rotary driving force from a drive shaft to a driven shaft in a vehicle such as an automobile. A bellows-shaped boot is attached to the constant velocity universal joint in order to reliably maintain the liquid tightness of the inside.
Specifically, one end of the boot is attached for closing an opening of a housing (outer cup) of the constant velocity universal joint. The other end of the boot is fitted on the outer circumference of the driven shaft.
A method of attaching the boot is known, in which a fixture formed of an annular iron plate is used. A part of the fixture is forcibly inserted or tightened on a shaft and an outer cup. An end of the boot is covered and tightened with another part of the fixture. Accordingly, the boot is attached to the shaft and the outer cup (see Japanese Laid-Open Utility Model Publication No. 4-7730).
In another method, a clamp ring having an inner diameter smaller than a diameter of a circumferential groove of a boot is forcibly inserted into the groove of the boot, thereby attaching the boot to the shaft and the outer cup (see Japanese Laid-Open Utility Model Publication No. 4-88722).
In the conventional methods of attaching the boot as described above, the boot attached to the outer cup is prevented from suffering any deviation by the clamp ring or the tightening portion of the fixture. However, the seal portion may be deviated due to secular changes, and the sealing function may be deteriorated for the lubricating oil enclosed in the outer cup.
A general object of the present invention is to provide an attachment structure for a joint boot, which makes it possible to reliably achieve the sealing function for the lubricating oil enclosed in an outer cup by avoiding any deviation of a seal portion even when the joint boot suffers from secular changes.
The above and other objects, features, and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings in which a preferred embodiment of the present invention is shown by way of illustrative example.